Plugin 'EasyMultiSave' failed to load because module 'EasyMultiSave' could not be found. Please ensure the plugin is properly installed, otherwise consider disabling the plugin for this project.

I packed the game, it doesn’t start, an error

are you using that plugin in game?

Yes

strange but packaging is done successful and when you try to play, this error is coming?

usually, this happens maybe when opening the project

I run the packaged game and the error, I run it in the editor, everything works

so i think while packaging, some setting has to be enabled i think regarding the plugin or adding of any directories related to that plugin as such i guess. Did you try contacting the plugin developer like their discord?